15/10/2026
Contrary to popular belief, there are 256 shades of grey!
The dynamic range on your ultrasound machine determines how many of these shades of grey you see in the image.
A higher range will display more shades of grey, giving the image a "smoother" appearance. A narrower range will display fewer shades of grey, giving a higher contrast image.
Echocardiography and musculoskeletal ultrasound require a lower dynamic range, whereas abdominal imaging requires a higher range.
Why? Well, when scanning the heart for example, you just need to see blood vs. valves (black vs. white), and emphasis is on having a high temporal resolution and maximising Doppler capability.
Meanwhile, when scanning the abdomen, you need to see subtle variations in soft tissue densities, and so you to see more shades of grey. Too high a range will "smooth" the image too much, reducing diagnostic information. ⠀
As with all aspects of ultrasound, finding the right balance with the dynamic range is the key to getting the best diagnostic information.